Heat the kidney beans in a saucepan over high, stirring, until most of the liquid has evaporated. I left at least 1/4 cup in there because I was in a hurry to get the rice cooking.
Add the coconut milk and rice and water (basically at a 2:1 ratio, but the cans keep shrinking!). Bring to a boil, stir, then cover, and lower to a simmer for 20-25 minutes. Add the salt and pepper now or at the table.